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Bactericidal effect on S. mutans using N-TiO2 with combined treatment of low concentration H2O2 and visible light
Seung-Yong Song1, Franklin Garcia-Godoy2,3, Yong Hoon Kwon4
1Department of Conservative Dentistry, School of Dentistry, Pusan National University, Pusan, Korea.
Purpose:
To test the feasibility of nitrogen-doped TiO₂ nanoparticles in the killing of Streptococcus mutans (S. mutans) for short term treatment.
Methods:
For the study, S. mutans were treated with the combinations of N-TiO₂, visible light, and without/with 0.5% H₂O₂ inclusion. Visible light was irradiated for 3 minutes one time.
Results:
Methylene blue solution was degraded (bleached) 5-30% by one of N-TiO₂ (or TiO₂) + visible laser (405 or 660 nm) +0.5% H₂O₂ conditions owing to almost linearly producing free radicals through photocatalysis. Antibacterial outcomes treated with N-TiO₂ were slightly better than those by TiO₂ regardless of test condition. Also, killing of S. mutans treated with 405 nm laser was slightly better than those by 660 nm laser.
Clinical Significance:
S. mutans can be eliminated using N-TiO₂ with clinically acceptable light (wavelength, intensity) and low concentration H₂O₂ condition under short term treatment.
